Table I.
Baseline characteristics of infants hospitalized for bronchiolitis by prenatal ASM exposure
| Demographic characteristics | Analytical cohort (n = 900) | ASM Exposed (n = 144) | ASM Unexposed (n = 756) | P value |
|---|---|---|---|---|
| Age at enrollment (mo), median (IQR) | 3.22 (1.67-6.00) | 3.42 (1.81-6.05) | 3.20 (1.64-5.93) | .48 |
| Sex | .61 | |||
| Female | 361 (40) | 55 (38) | 306 (40) | |
| Male | 539 (60) | 89 (62) | 450 (60) | |
| Race/ethnicity | <.001 | |||
| Non-Hispanic white | 396 (44) | 93 (65) | 303 (40) | |
| Non-Hispanic black | 201 (22) | 22 (15) | 179 (24) | |
| Hispanic | 268 (30) | 27 (19) | 241 (32) | |
| Other | 35 (4) | 2 (1) | 33 (4) | |
| Insurance status | <.001 | |||
| Private | 367 (41) | 88 (61) | 279 (37) | |
| Public | 519 (58) | 54 (38) | 465 (62) | |
| Uninsured | 12 (1) | 2 (1) | 10 (1) | |
| Median household income | .03 | |||
| <$40,000 per year | 304 (34) | 37 (26) | 267 (35) | |
| ≥$ 40,000 per year | 596 (66) | 107 (74) | 489 (65) | |
| Gestational age at birth (wk) | <.001 | |||
| >40 | 352 (39) | 38 (26) | 314 (42) | |
| >37-40 | 382 (42) | 59 (41) | 323 (43) | |
| >34-37 | 134 (15) | 39 (27) | 95 (13) | |
| >32-34 | 32 (4) | 8 (6) | 24 (3) | |
| Birth weight (lb) | .15 | |||
| <5 | 57 (6) | 13 (9) | 44 (6) | |
| ≥5 | 838 (94) | 131 (91) | 707 (94) | |
| Mode of delivery | .07 | |||
| Vaginal | 589 (66) | 85 (59) | 504 (67) | |
| C-Section | 310 (34) | 59 (41) | 251 (33) | |
| Multiple birth (ie, twin) | <.001 | |||
| Yes | 41 (5) | 16 (11) | 25 (3) | |
| No | 859 (95) | 128 (89) | 731 (97) | |
| Maternal antibiotics before labor | .004 | |||
| Yes | 242 (27) | 52 (37) | 190 (25) | |
| No | 647 (73) | 88 (63) | 559 (75) | |
| Maternal smoking during pregnancy | .16 | |||
| Yes | 123 (14) | 25 (17) | 98 (13) | |
| No | 776 (86) | 119 (83) | 657 (87) | |
| Maternal history of asthma | .002 | |||
| Yes | 192 (21) | 45 (31) | 147 (20) | |
| No | 702 (79) | 98 (69) | 604 (80) | |
| Maternal history of atopic condition∗ | <.001 | |||
| Yes | 208 (23) | 50 (35) | 158 (21) | |
| No | 689 (77) | 93 (65) | 596 (79) |
C-section, Cesarean section; IQR, interquartile range.
Data are expressed as n (%) unless otherwise indicated.
∗
Atopic conditions include asthma, allergic rhinitis, food allergy, and eczema.